High-Speed Memory: 6 Technologies to Watch

When it comes to developments in high-speed memory, a lot of the focus is turning to DDR4 as it moves into high-level production this year. However, there are several other trends to watch as well. EE Times is highlighting six to watch.

Do you know how fast the latest DDR4 memories are, or how many transistors make up a high speed SRAM cell? The latest high-speed memories are boosting the performance of servers, systems, and SoCs. Here are six of the latest technologies, from DDR4 to embedded DRAM and various SRAM cells, well as the latest technology from memory specialist Rambus.

To find out what’s hot in high-speed memory, click on the first picture to start the image gallery:

DDR4

The latest high speed dynamic memory technology is DDR4, set to reach the market in volume later this year. The specification started in 2005 in order to deliver faster clock frequencies, to provide higher data rates of 4266 MT/s (up from 2133 Mtransfers/s for DDR3), and to support lower voltages of 1.05 to 1.2V in new chipsets. The new standard also includes Connectivity Test, a type of JTAG boundary scan that boosts device and module manufacturing testing by enabling early fault detection in order to reduce time spent on debugging and improve system reliability. Samsung started production of 4G DDR4 devices on 20nm in September 2013, while Micron Technologies, which now includes Elpida, is shipping 8G and 4G DDR4 devices.

3D Memory, with its two flavors HMC and HBM, will become the high speed memory of future. They will replace DDR technolog in server application. Besides providing much higher bandwidth than DDR4 (4x to 6x), HMC makes the job of PCB designer easier becuase it is based of serial interface technology where as DDR4 is based on parallel interface technology. But the question is when. There are two challenges. First one is cost, HMC is at least 3x costlier (if not more) than DDR4. And it is not pin replacable, creating the need of fresh board design. Server has long product lifetime, hence this is a challenge to HMC adoption

These aren't even technologies to watch - they are interface solutions to consider. No, I won't put DDR4 in my smartphone. No, I won't put embedded DRAM in my server, etc. Since this article was about 'memory interconnect technologies to watch', why is a serial connected RAM interface like HMC not even mentioned?